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NHS Sustainable Development: 14th February 2012

‘Reduce Energy Consumption Through Steam System Modernisation’

Presentation by: Andy BennettNational Key Account Manager

Overview1. Thermal Energy International – Who Are We?2. Government Energy Reduction Targets3. Why is steam still used in Industry?4. Steam system Walkthrough5. Key components of the steam system

1. Boiler2. Steam distribution system3. Heat exchangers4. Steam Traps5. Condensate return system6. Hotwell

6. Where do these energy losses occur7. How to fund these improvements

Thermal Energy International• Committed to reducing waste energy and reducing consumption

through steam system modernisation

• Two key product ranges– GEM Condensate Return Systems– Flu Ace Flue Gas Condensing Economisers

• Working closely within a variety of industries with– Private Sector Organisations– Public Sector Organisations

Government Targets

How Can These Targets Be Achieved?

• Climate Change ACT• Carbon Budgets• SOGE Targets• CRC Energy Efficiency Scheme – 20,000 large private and public

sector organisations are involved in the CRC Energy Efficiency Scheme

Source: www.decc.gov.uk

Year Target

2020 34% Reduction

2050 80% Reduction

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Best Practice in steam system operation↑ Efficiency

↑ Productivity

↓ Costs

↓ CO2 Emissions

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Best Practice in steam system operation↓ CO2 Emissions

↓ Costs

↑ Efficiency

Productivity

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Why use steam? More efficient

Available energy

0

500

1000

1500

2000

2500

3000

1 5 10 20Steam Pressure (bar)

Ener

gy (k

j/kg)

LatentSensible

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Why use steam? More practical• Easy to control –

temperature / pressure relationship

• Relatively constant temperature

• High temperatures

• Non toxic

• Freely Available

Variation of temperature with steam pressure

0

50

100

150

200

250

300

0 10 20 30 40 50 60

Steam Pressure (bar)

Stea

m T

empe

ratu

re (º

C)

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Steam system walk through

Boiler

HotwellCondensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Boiler heat lossesBoiler Flue gasses 18%

ShellLosses 4%

Fuel100%

Blow down 3%

Steam 75%

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Boiler economiserConventional Economiser

Extract sensible heat from flue gassesLimited by the dew point temperatureUsed for preheating boiler feed waterTypical savings = 2 to 4 %

Condensing Economiser – Heat RecoveryExtract sensible and latent heatLimited to gas boilersLower heat recovery temperatureTypical savings = 15-18 %

Condensing Heat Recovery System

Waste Flue Gas Sources:

• Institutional & Industrial Boilers

• Gas Turbine or Engine Cogen

Energy Recycling for:

• Process Make-up Water • Heating

• Boiler Make-up Water Heating

• Process Liquid Heating

• Dryer Make-up Air Heating

• Combustion Air Heating

• Ventilation Make-up Air • Heating

• Mixed Air Heating

• Perimeter Radiation Heating

• Domestic Hot Water Heating

15% to 18% Typical Energy Savings

How FLU-ACE® Works• Extract Sensible and Latent

Heat

• The blue area to the right represents latent heat, the brown area sensible heat

• Heated water is circulated at up to 65°C to various heat users

• With indirect design the primary circuit water can be raised to 90°C

175 C 150 C 125 C 100 C 75 C 50 C

Exhaust Gas Temperature

Flu Gas Economiser – Case Study

Benefits

• 3 Hospitals Converted• £400,000 + saved annually in

energy• Payback within 12 months.

Belfast NHS Trust

Flu Gas Economiser – Case Study

Benefits

• Recently Converted• Savings of 1.5mW/h, • Circa £330,000 + saved annually in

energy• Payback reduced by 12 months from

original estimate.

St George’s Healthcare NHS Trust

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Steam Distribution system

Steam mains contain;• Steam

• Condensate

• Air

• Dirt / debris

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Dirt pockets

• Every 30-40m (more frequently on uphill sections)

• Before a rise

• Before CV’s and PRV’s

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Insulation

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Steam system walk through – Heat exchangers

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Plate vs. Shell and Tube heat exchangers

Plate heat exchangers

+ Improve heat transfer, compact, more responsive, no annual pressure tests

- More susceptible to leaks, small diameter flow paths

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Plate vs. Shell and Tube heat exchangers

S & T heat exchangers+ More robust design, can cope with suspended solids, no leaks- High surface heat losses, bigger footprint

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

What is a steam trap?• Differentiates between steam and condensate

• Discharges condensate, air and incondensable gasses

• Retains steam within the system until it has given up its energy

Types of steam trap• Mechanical Oversized orifice, opening and closing mechanism

– Float– TD– Inverted Bucket

• Orifice plate – Sized orifice, Constant conditions• Venturi orifice – Sized orifice, self regulating over varying loads

Float TrapE

A

C

DB

Types of mechanical traps

Inverted Bucket TrapTypes of mechanical traps

Problems with mechanical traps

• Parts, Parts and More Parts• High Failure Rates – Typically 10%

per year• Oversized Orifice, Significant

Failure Path for Steam• Complex Mechanisms, Millions of

Cycles• Live Steam Passes to Operate Trap

by Design

Losses through failed trapsTrap size

Orifice dia (mm) Steam loss kg/hr6 barg 14 barg 32 barg

DN15 3 8 19 43DN20 5 24 53 119DN25 7.5 55 121 270DN40 10 98 214 478DN50 12.5 152 335 747

No of traps on site = 150Average size = DN20Steam pressure = 6 bargSteam loss/ failed trap = 24 kg/hr* Reference Spirax Sarco website

Losses through failed trapsAnnual steam loss

3,132 tonnes/yrSteam cost

£20/tonne Cost of failed traps

£62,640/yrPlus 476 tonnes CO2 / yr

Equivalent to removing 144 cars off the road!

The GEM Venturi Steam Trap

How Does The GEM Trap Work?

High PressureLow Pressure

Steam Condensate

FLOW

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University lab results: Most efficient over variable loads

IB

Free Float

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0 20 40 60 80 100 120 140 160Condensate flow (expressed as flow level in cm of liquid in evaporative column of test rig (cm))

Stea

m lo

ss (k

g hr

-1)

Float trap

TD

MK

BPT

GEM

The Operational Benefits of the GEM trap system

• No moving parts = increased reliability• Energy Savings of 11% +• Permanently Eliminates Live Steam Loss• 10 year performance guarantee• Project Payback Typically 12 – 24 months

GEM® Condensate Return System – Case StudySalisbury District Hospital

Benefits

• Eradicated steam trap failure• 10% Reduction In Steam

Consumption• £40,000 Saved Annually• Project Payback Within 18

months

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Condensate return systemRecycles the remaining energy in the condensateby returning it to the hotwell – 3 main types:

1. Discharge to drain – total loss of all energy and treated water2. Vented return system – reuses condensate and sensible heat3. Pressurised return – Reuses the condensate, sensible heat and

flash steam

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Flash steam recovery check listNeed a low pressure application

– Similar demand profile– Located close to high pressure system

Flash vessel require insurance inspections

Examples– Large air heaters– Boiler feedwater temperature increase– Space heating systems (seasonal)

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Steam system walk through

Boiler

Hotwell

Condensate Return

Steam Trap

Heat Exchanger

Distribution systemDistribution system

Boiler

Distribution system

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Steam system walkthrough - Hotwell

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

18 % stack losses

3% standing loss 2 % blowdown

loss

5% condensate loss/flash

5% pipework insulation

loss

10% steam trap loss

2% pipe leakage

100% fuel input 55% useful heat output

Energy Losses In A Typical Steam System

TEI can recover

•Steam Traps – 10%•Stack Loss – 18%•Flash Steam – 5%•Boiler Blowdown – 2%•Insulation – 5%

40%For every £1 spent on fuel you only get 55p of useful energy!!!

For every £1 spent on fuel you get 95p of useful energy!!!

How To Fund These Improvements

Subscription

Immediate savings

Subscription is a managed service paid for out of savings

Includes everythingUse of EquipmentSupportMaintenanceReplacement parts

Subscription

….it’s all about SERVICE

Subscription PrinciplesSubscription puts focus on benefits and

delivers a service capability

All-inclusivesubscription

installationHardwareSystems

On-going Services

Supplier CustomerCUSTOMER

No customer ownership

“ If it appreciates, buy it;If it depreciates, rent it”

J. Paul Getty

EVERY DAY YOUR MONEYIS GOING DOWN THE DRAIN

WHEN

The Thermal Energy managed service will cut your energy cost

and reduce your carbon footprint

WITHOUT INVESTING A PENNY.

The message is.........

Private Finance – Capital Purchase

Example – Capital PurchaseCapital Cost = £100,000Energy Savings Per Year = £50,000Project Payback = 2 Years

ON BALANCE SHEET REQUIRES CAPITAL SANCTION. COST NEGATIVE FOR 2 YEARS

5 year rental paid quarterly inline with savings = £22,000 per yearEnergy Savings Per Year = £50,000Net Annual Saving = £28,000

• OFF BALANCE SHEET OPERATING LEASE• RENTALS OUT OF SAME OPERATING BUDGET THAT ARE MAKING

THE SAVINGS • CASH POSITIVE FROM THE START• NO DEPRECIATING ASSETS• QUICK DECISION• AFTER 5 YEARS HAVE OPTION OF TERMINATING RENTAL,

CONTINUATION AT REDUCED FAIR MARKET VALUE RENTAL , OR CAN REFRESH THE TECHNOLOGY ON NEW AGREEMENT

Subscription Example

Impacting Your Emissions Targets

15%

26-34%

80%

Further reducing up to19% of overall carbon emissions through steam system modernisation

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NHS Sustainable Development: 14th February 2012

Case Study: Royal National Orthopaedic Hospital, Stanmore

Presentation by: Matthew HardyGeneral Manager (Estates)

• Used on RNOH since 1998

• No trap Maintenance required

• Energy and Carbon Reduction

• 10 year Guarantee

• Sized for each application

GEM® Condensate Return SystemRoyal National Orthopaedic Hospital, Stanmore

GEM® Condensate Return System

Benefits

• Circa 10% Reduction In Steam Consumption

• Circa 10% Reduction In Carbon Emissions

• Project Payback Within 18 months

Royal National Orthopaedic Hospital, Stanmore

• Recovering waste Heat for Boiler Flues

• Preheats Boiler Feed water and tops up Hydronic loop

• Reduces load on Boilers

• Includes kWh and Carbon metering

Royal National Orthopaedic Hospital, StanmoreCondensing Heat Recovery System

Benefits

• 578 Tonne Reduction In Carbon Emissions Per Year

• £68,929 Saved Annually

• Looking at extending heat use for further savings

Condensing Heat Recovery SystemRoyal National Orthopaedic Hospital, Stanmore

Any Questions?

Stand 16: The Brewery